As of 2006, the number of pets in the United States outnumbered the number of people by 60 million, resulting in over $35 billion spent by US consumers per year on pet care. A significant portion of these pet care costs are spent on pet foods. In recent years, an emphasis has been placed on developing healthier and more palatable pet foods. Less work, however, has been directed to the methods used to make these pet foods. With such a large amount of money spent per year on pet foods, improved methods for their manufacture could result in substantial increases in profit margins for pet food manufacturers.
Often, traditional pet foods are formed by extrusion: ingredients are mixed and passed through an extruder, and the resultant extrudate passes through a nozzle, is cut to a certain size, and subsequently dried. Although this method is suitable for high throughput formation of large quantities of pet foods, the resultant product is usually in the form of a basic, low-resolution shape such as a cylinder or sphere.
When pet foods with intricate shapes and high-resolution structures are desired, extrusion techniques are not suitable and alternative techniques such as die stamping, forging, book molding, and injection molding are used. These alternative techniques are often time consuming, lead to large amounts of waste, and are not conducive to high-throughput manufacturing. Improvements to pet food manufacturing technology would be desirable.